A pneumothorax can be primary or secondary. A high proportion of patients with secondary spontaneous pneumothorax are the elderly who are in poor general condition due to their impaired cardiac and pulmonary functions as well as due to other complications. Therefore, it may be difficult for these patients to undergo surgical procedures; in addition, the elderly may be at high risk for postoperative pulmonary fistula due to severe adhesions and emphysema complications. These non-operative and high-risk cases may be treated with pleurodesis (a procedure that involves instillation of a chemical or irritant into the thoracic cavity through an injection), bronchoscopic bronchial embolisation, or other procedures. In Japan, no device is currently approved for performing pleurodesis, but an approval of one device is expected soon. This will be an open-label, single-arm multicentre study conducted among 30 patients with secondary intractable pneumothorax who are not indicated to undergo surgery. The primary endpoint will be presence or absence of chest tube removal. The secondary endpoints will be the disappearance/decrease of air leakage, grade of dyspnoea, and duration of drainage. This study will assess the safety and efficacy of sterile graded talc pleurodesis in patients with secondary intractable pneumothorax.